Breast cancer incidence rates are relatively high in women. Nearly 1 in 8 women in the western world and nearly 1 in 11 women in India will have breast cancer. In the western world, it is the leading cancer in women. In India, for example, it is the second after cervical cancer. Early detection is key to survival as the mortality rates are high for advanced stages. Mammography is considered the gold standard for breast cancer screening. Screening for breast cancers are commonly done via manual detection of a lump in the breast tissue and/or by an in-office mammography exam followed by human interpretation of the image created during the examination. In the mammography exam, the subject is subjected to highly personal physical contact and a procedure which many subjects find discomforting. In subjects with dense breast tissue, the exam may not be as effective in spotting malignancies as for other subjects. Moreover, the equipment required for mammography is relatively large and relatively expensive. Since mammography is an x-ray machine it cannot be used at homes without supervision. The x-ray radiation itself may result in cancer. It is also not effective for younger women due to the dense breast tissue. There is also some evidence that the physical manipulation of the breast tissue during mammography could rupture the malignant cysts, thereby increasing risk of spreading the malignant cells to other tissues and into the subject's blood stream.
Thermography is an emerging alternative non-invasive and non-contact screening method for breast cancer detection. Thermal imaging captures the infra-red emissivity from the human body in the 7-10 μm wavelength range. Thermal imaging devices are useful for the detection of thermal activity in breast tissue due to a tumor's growth being enabled by causing new blood vessels to grow disproportionately through angiogenesis in the area of the tumor relative to surrounding tissue. This increased biophysical activity beneath the skin surface associated with tumor growth results in a higher metabolic rate which, in turn, results in an elevated temperature in that tissue. This appears as a hotspot in a thermal image containing that tissue. Recently, interest has been rekindled in thermography as a breast cancer screening approach with the improvement in thermal camera resolution and technology.
Trained radiologists and thermographers look for these abnormalities in thermal images to make a determination whether tissue is cancerous or is suspicious of being cancerous. If so, the subject may need to undergo additional tests, such as sonomammography followed by cancer diagnosis through histopathology by fine needle aspiration cytology or tissue biopsy. Thermographers and radiologists are increasingly demanding more powerful visualization software interface tools to assist them. Moreover, since medical practitioners trained in thermography are not readily available in rural areas in emerging markets like India, automatic screening tools will help open up these market for software applications for breast cancer screening and detection.
Accordingly, what is needed in this art are increasingly software tools which enable subjects as well as medical practitioners to manually or automatically analyze a thermal image of an area of breast tissue for the presence of cancerous tissue.